[SERIAL] ip22zilog: Fix oops on runlevel change with serial console

[mirror_ubuntu-bionic-kernel.git] / drivers / serial / ip22zilog.c

diff --git a/drivers/serial/ip22zilog.c b/drivers/serial/ip22zilog.c
index ef132349f310d8325122458bea12b52b039d696e..193722d680cf25f5ce42b1c1fa0e1c531940ac0b 100644 (file)
--- a/drivers/serial/ip22zilog.c
+++ b/drivers/serial/ip22zilog.c
@@ -215,7 +215,7 @@ static void __load_zsregs(struct zilog_channel *channel, unsigned char *regs)
        /* Lower and upper byte of baud rate generator divisor.  */
        write_zsreg(channel, R12, regs[R12]);
        write_zsreg(channel, R13, regs[R13]);
-       
+
        /* Now rewrite R14, with BRENAB (if set).  */
        write_zsreg(channel, R14, regs[R14]);
 
@@ -259,13 +259,7 @@ static void ip22zilog_receive_chars(struct uart_ip22zilog_port *up,
        struct tty_struct *tty = up->port.info->tty;    /* XXX info==NULL? */
 
        while (1) {
-               unsigned char ch, r1;
-
-               if (unlikely(tty->flip.count >= TTY_FLIPBUF_SIZE)) {
-                       tty->flip.work.func((void *)tty);
-                       if (tty->flip.count >= TTY_FLIPBUF_SIZE)
-                               return;         /* XXX Ignores SysRq when we need it most. Fix. */
-               }
+               unsigned char ch, r1, flag;
 
                r1 = read_zsreg(channel, R1);
                if (r1 & (PAR_ERR | Rx_OVR | CRC_ERR)) {
@@ -303,8 +297,7 @@ static void ip22zilog_receive_chars(struct uart_ip22zilog_port *up,
                }
 
                /* A real serial line, record the character and status.  */
-               *tty->flip.char_buf_ptr = ch;
-               *tty->flip.flag_buf_ptr = TTY_NORMAL;
+               flag = TTY_NORMAL;
                up->port.icount.rx++;
                if (r1 & (BRK_ABRT | PAR_ERR | Rx_OVR | CRC_ERR)) {
                        if (r1 & BRK_ABRT) {
@@ -321,28 +314,21 @@ static void ip22zilog_receive_chars(struct uart_ip22zilog_port *up,
                                up->port.icount.overrun++;
                        r1 &= up->port.read_status_mask;
                        if (r1 & BRK_ABRT)
-                               *tty->flip.flag_buf_ptr = TTY_BREAK;
+                               flag = TTY_BREAK;
                        else if (r1 & PAR_ERR)
-                               *tty->flip.flag_buf_ptr = TTY_PARITY;
+                               flag = TTY_PARITY;
                        else if (r1 & CRC_ERR)
-                               *tty->flip.flag_buf_ptr = TTY_FRAME;
+                               flag = TTY_FRAME;
                }
                if (uart_handle_sysrq_char(&up->port, ch, regs))
                        goto next_char;
 
                if (up->port.ignore_status_mask == 0xff ||
-                   (r1 & up->port.ignore_status_mask) == 0) {
-                       tty->flip.flag_buf_ptr++;
-                       tty->flip.char_buf_ptr++;
-                       tty->flip.count++;
-               }
-               if ((r1 & Rx_OVR) &&
-                   tty->flip.count < TTY_FLIPBUF_SIZE) {
-                       *tty->flip.flag_buf_ptr = TTY_OVERRUN;
-                       tty->flip.flag_buf_ptr++;
-                       tty->flip.char_buf_ptr++;
-                       tty->flip.count++;
-               }
+                   (r1 & up->port.ignore_status_mask) == 0)
+                       tty_insert_flip_char(tty, ch, flag);
+
+               if (r1 & Rx_OVR)
+                       tty_insert_flip_char(tty, 0, TTY_OVERRUN);
        next_char:
                ch = readb(&channel->control);
                ZSDELAY();
@@ -434,10 +420,8 @@ static void ip22zilog_transmit_chars(struct uart_ip22zilog_port *up,
        if (up->port.info == NULL)
                goto ack_tx_int;
        xmit = &up->port.info->xmit;
-       if (uart_circ_empty(xmit)) {
-               uart_write_wakeup(&up->port);
+       if (uart_circ_empty(xmit))
                goto ack_tx_int;
-       }
        if (uart_tx_stopped(&up->port))
                goto ack_tx_int;
 
@@ -585,7 +569,7 @@ static void ip22zilog_set_mctrl(struct uart_port *port, unsigned int mctrl)
        else
                clear_bits |= DTR;
 
-       /* NOTE: Not subject to 'transmitter active' rule.  */ 
+       /* NOTE: Not subject to 'transmitter active' rule.  */
        up->curregs[R5] |= set_bits;
        up->curregs[R5] &= ~clear_bits;
        write_zsreg(channel, R5, up->curregs[R5]);
@@ -668,7 +652,7 @@ static void ip22zilog_enable_ms(struct uart_port *port)
        if (new_reg != up->curregs[R15]) {
                up->curregs[R15] = new_reg;
 
-               /* NOTE: Not subject to 'transmitter active' rule.  */ 
+               /* NOTE: Not subject to 'transmitter active' rule.  */
                write_zsreg(channel, R15, up->curregs[R15]);
        }
 }
@@ -694,7 +678,7 @@ static void ip22zilog_break_ctl(struct uart_port *port, int break_state)
        if (new_reg != up->curregs[R5]) {
                up->curregs[R5] = new_reg;
 
-               /* NOTE: Not subject to 'transmitter active' rule.  */ 
+               /* NOTE: Not subject to 'transmitter active' rule.  */
                write_zsreg(channel, R5, up->curregs[R5]);
        }